Guardian.co.uk remained the most popular UK newspaper website last month with more than 31 million monthly unique users, despite shedding more than 1 million uniques after September's record traffic.

Mail Online and Telegraph.co.uk also stayed above 30 million unique users for the second month running, according to the latest figures from the Audit Bureau of Circulations Electronic published today.

Guardian News & Media's website network, theguardian.com, which includes content from the Observer and MediaGuardian.co.uk, attracted 31,693,844 unique users in October, down 3.82% on September, but up 22% year on year.

"Our Trafigura story and Charlie Brooker's column on Jan Moir a few days later highlighted the way stories can grow and propagate through Twitter and Facebook with steady streams of traffic being driven by these social media channels," said Emily Bell, director of digital content at GNM. "Guardian.co.uk then provided the perfect space for readers to add their comments and opinions."

At Mail Online, Daily Mail & General Trust's website network, traffic grew by 1.33% month on month to 30,441,081 global unique users last month, with strong growth of 43.62% from a year ago. Mail Online also moved ahead of Telegraph.co.uk last month.

Telegraph.co.uk slipped back to third place as unique user numbers fell 3.24% between September and October to 30,012,735. This represented a 29.32% year-on-year increase.

Mirror Group Digital's network of sites, which includes Mirror.co.uk, posted the largest growth among national newspaper websites in October with a 13.61% increase month on month and a 74% rise year on year to move above the 10 million unique-user barrier.

News International, which has shifted its focus away from driving user numbers as it plots the implementation of paywalls, experienced vastly contrasting fortunes last month.

News International's Sun Online, which incorporates page3.com and News of the World content, experienced a drop of 9.37% month on month, the largest drop among UK newspaper websites, to 20,839,831 users in October. This represented a 21.67% increase year on year.

Times Online leapfrogged its News International stablemate to become the fourth most popular UK newspaper website last month, recording a 12.8% month-on-month increase in unique users to 20,872,089. This represents a 1.94% year-on-year increase.

Independent.co.uk also performed well in October boosting unique users by 10.43% month on month to 9,703,508 - a 15.4% year-on-year increase.

The Guardian was also the biggest UK newspaper website in terms of UK unique users, with 13,290,715 last month.

Mail Online weighed in second with 11,200,200 UK unique users. Telegraph.co.uk ranked third with 10,119,699, Sun Online fourth with 9,325,768, Times Online fifth with 7,594,577, Mirror Group sixth with 5,845,507 and the Independent seventh with 3,960,256.

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